aboutsummaryrefslogtreecommitdiffstats
path: root/arch/powerpc/kernel/machine_kexec.c
blob: 7ee50f0547cb73de52be535b8f4b6543536b5405 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
/*
 * Code to handle transition of Linux booting another kernel.
 *
 * Copyright (C) 2002-2003 Eric Biederman  <ebiederm@xmission.com>
 * GameCube/ppc32 port Copyright (C) 2004 Albert Herranz
 * Copyright (C) 2005 IBM Corporation.
 *
 * This source code is licensed under the GNU General Public License,
 * Version 2.  See the file COPYING for more details.
 */

#include <linux/kexec.h>
#include <linux/reboot.h>
#include <linux/threads.h>
#include <linux/memblock.h>
#include <linux/of.h>
#include <linux/irq.h>
#include <linux/ftrace.h>

#include <asm/machdep.h>
#include <asm/prom.h>
#include <asm/sections.h>

void machine_kexec_mask_interrupts(void) {
	unsigned int i;

	for_each_irq(i) {
		struct irq_desc *desc = irq_to_desc(i);
		struct irq_chip *chip;

		if (!desc)
			continue;

		chip = irq_desc_get_chip(desc);
		if (!chip)
			continue;

		if (chip->irq_eoi && irqd_irq_inprogress(&desc->irq_data))
			chip->irq_eoi(&desc->irq_data);

		if (chip->irq_mask)
			chip->irq_mask(&desc->irq_data);

		if (chip->irq_disable && !irqd_irq_disabled(&desc->irq_data))
			chip->irq_disable(&desc->irq_data);
	}
}

void machine_crash_shutdown(struct pt_regs *regs)
{
	default_machine_crash_shutdown(regs);
}

/*
 * Do what every setup is needed on image and the
 * reboot code buffer to allow us to avoid allocations
 * later.
 */
int machine_kexec_prepare(struct kimage *image)
{
	if (ppc_md.machine_kexec_prepare)
		return ppc_md.machine_kexec_prepare(image);
	else
		return default_machine_kexec_prepare(image);
}

void machine_kexec_cleanup(struct kimage *image)
{
}

void arch_crash_save_vmcoreinfo(void)
{

#ifdef CONFIG_NEED_MULTIPLE_NODES
	VMCOREINFO_SYMBOL(node_data);
	VMCOREINFO_LENGTH(node_data, MAX_NUMNODES);
#endif
#ifndef CONFIG_NEED_MULTIPLE_NODES
	VMCOREINFO_SYMBOL(contig_page_data);
#endif
}

/*
 * Do not allocate memory (or fail in any way) in machine_kexec().
 * We are past the point of no return, committed to rebooting now.
 */
void machine_kexec(struct kimage *image)
{
	int save_ftrace_enabled;

	save_ftrace_enabled = __ftrace_enabled_save();

	if (ppc_md.machine_kexec)
		ppc_md.machine_kexec(image);
	else
		default_machine_kexec(image);

	__ftrace_enabled_restore(save_ftrace_enabled);

	/* Fall back to normal restart if we're still alive. */
	machine_restart(NULL);
	for(;;);
}

void __init reserve_crashkernel(void)
{
	unsigned long long crash_size, crash_base;
	int ret;

	/* this is necessary because of memblock_phys_mem_size() */
	memblock_analyze();

	/* use common parsing */
	ret = parse_crashkernel(boot_command_line, memblock_phys_mem_size(),
			&crash_size, &crash_base);
	if (ret == 0 && crash_size > 0) {
		crashk_res.start = crash_base;
		crashk_res.end = crash_base + crash_size - 1;
	}

	if (crashk_res.end == crashk_res.start) {
		crashk_res.start = crashk_res.end = 0;
		return;
	}

	/* We might have got these values via the command line or the
	 * device tree, either way sanitise them now. */

	crash_size = crashk_res.end - crashk_res.start + 1;

#ifndef CONFIG_RELOCATABLE
	if (crashk_res.start != KDUMP_KERNELBASE)
		printk("Crash kernel location must be 0x%x\n",
				KDUMP_KERNELBASE);

	crashk_res.start = KDUMP_KERNELBASE;
#else
	if (!crashk_res.start) {
		/*
		 * unspecified address, choose a region of specified size
		 * can overlap with initrd (ignoring corruption when retained)
		 * ppc64 requires kernel and some stacks to be in first segemnt
		 */
		crashk_res.start = KDUMP_KERNELBASE;
	}

	crash_base = PAGE_ALIGN(crashk_res.start);
	if (crash_base != crashk_res.start) {
		printk("Crash kernel base must be aligned to 0x%lx\n",
				PAGE_SIZE);
		crashk_res.start = crash_base;
	}

#endif
	crash_size = PAGE_ALIGN(crash_size);
	crashk_res.end = crashk_res.start + crash_size - 1;

	/* The crash region must not overlap the current kernel */
	if (overlaps_crashkernel(__pa(_stext), _end - _stext)) {
		printk(KERN_WARNING
			"Crash kernel can not overlap current kernel\n");
		crashk_res.start = crashk_res.end = 0;
		return;
	}

	/* Crash kernel trumps memory limit */
	if (memory_limit && memory_limit <= crashk_res.end) {
		memory_limit = crashk_res.end + 1;
		printk("Adjusted memory limit for crashkernel, now 0x%llx\n",
		       (unsigned long long)memory_limit);
	}

	printk(KERN_INFO "Reserving %ldMB of memory at %ldMB "
			"for crashkernel (System RAM: %ldMB)\n",
			(unsigned long)(crash_size >> 20),
			(unsigned long)(crashk_res.start >> 20),
			(unsigned long)(memblock_phys_mem_size() >> 20));

	memblock_reserve(crashk_res.start, crash_size);
}

int overlaps_crashkernel(unsigned long start, unsigned long size)
{
	return (start + size) > crashk_res.start && start <= crashk_res.end;
}

/* Values we need to export to the second kernel via the device tree. */
static phys_addr_t kernel_end;
static phys_addr_t crashk_size;

static struct property kernel_end_prop = {
	.name = "linux,kernel-end",
	.length = sizeof(phys_addr_t),
	.value = &kernel_end,
};

static struct property crashk_base_prop = {
	.name = "linux,crashkernel-base",
	.length = sizeof(phys_addr_t),
	.value = &crashk_res.start,
};

static struct property crashk_size_prop = {
	.name = "linux,crashkernel-size",
	.length = sizeof(phys_addr_t),
	.value = &crashk_size,
};

static void __init export_crashk_values(struct device_node *node)
{
	struct property *prop;

	/* There might be existing crash kernel properties, but we can't
	 * be sure what's in them, so remove them. */
	prop = of_find_property(node, "linux,crashkernel-base", NULL);
	if (prop)
		prom_remove_property(node, prop);

	prop = of_find_property(node, "linux,crashkernel-size", NULL);
	if (prop)
		prom_remove_property(node, prop);

	if (crashk_res.start != 0) {
		prom_add_property(node, &crashk_base_prop);
		crashk_size = crashk_res.end - crashk_res.start + 1;
		prom_add_property(node, &crashk_size_prop);
	}
}

static int __init kexec_setup(void)
{
	struct device_node *node;
	struct property *prop;

	node = of_find_node_by_path("/chosen");
	if (!node)
		return -ENOENT;

	/* remove any stale properties so ours can be found */
	prop = of_find_property(node, kernel_end_prop.name, NULL);
	if (prop)
		prom_remove_property(node, prop);

	/* information needed by userspace when using default_machine_kexec */
	kernel_end = __pa(_end);
	prom_add_property(node, &kernel_end_prop);

	export_crashk_values(node);

	of_node_put(node);
	return 0;
}
late_initcall(kexec_setup);